Sto provando a recuperare un file da un server usando SFTP (al contrario di FTPS) usando Java. Come posso fare questo?
Sto provando a recuperare un file da un server usando SFTP (al contrario di FTPS) usando Java. Come posso fare questo?
Risposte:
Un'altra opzione è quella di considerare la libreria JSch . JSch sembra essere la libreria preferita per alcuni grandi progetti open source, tra cui Eclipse, Ant e Apache Commons HttpClient, tra gli altri.
Supporta bene sia gli accessi utente / pass sia quelli basati su certificati, oltre a tutta una serie di altre gustose funzionalità SSH2.
Ecco un semplice recupero di file remoto su SFTP. La gestione degli errori viene lasciata come esercizio per il lettore :-)
JSch jsch = new JSch();
String knownHostsFilename = "/home/username/.ssh/known_hosts";
jsch.setKnownHosts( knownHostsFilename );
Session session = jsch.getSession( "remote-username", "remote-host" );
{
// "interactive" version
// can selectively update specified known_hosts file
// need to implement UserInfo interface
// MyUserInfo is a swing implementation provided in
// examples/Sftp.java in the JSch dist
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
// OR non-interactive version. Relies in host key being in known-hosts file
session.setPassword( "remote-password" );
}
session.connect();
Channel channel = session.openChannel( "sftp" );
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remote-file", "local-file" );
// OR
InputStream in = sftpChannel.get( "remote-file" );
// process inputstream as needed
sftpChannel.exit();
session.disconnect();
Ecco il codice sorgente completo di un esempio che utilizza JSch senza doversi preoccupare del controllo dei tasti ssh.
import com.jcraft.jsch.*;
public class TestJSch {
public static void main(String args[]) {
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("username", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remotefile.txt", "localfile.txt");
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
}
}
finally
necessario utilizzare un blocco per includere il codice di pulizia del canale, per garantire che sia sempre in esecuzione.
com.jcraft.jsch.JSchException: Session.connect: java.security.InvalidAlgorithmParameterException: Prime size must be multiple of 64, and can only range from 512 to 2048 (inclusive)
Di seguito è riportato un esempio che utilizza Apache Common VFS:
FileSystemOptions fsOptions = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(fsOptions, "no");
FileSystemManager fsManager = VFS.getManager();
String uri = "sftp://user:password@host:port/absolute-path";
FileObject fo = fsManager.resolveFile(uri, fsOptions);
Questa era la soluzione che mi è venuta in mente http://sourceforge.net/projects/sshtools/ (la maggior parte della gestione degli errori è stata omessa per chiarezza). Questo è un estratto dal mio blog
SshClient ssh = new SshClient();
ssh.connect(host, port);
//Authenticate
PasswordAuthenticationClient passwordAuthenticationClient = new PasswordAuthenticationClient();
passwordAuthenticationClient.setUsername(userName);
passwordAuthenticationClient.setPassword(password);
int result = ssh.authenticate(passwordAuthenticationClient);
if(result != AuthenticationProtocolState.COMPLETE){
throw new SFTPException("Login to " + host + ":" + port + " " + userName + "/" + password + " failed");
}
//Open the SFTP channel
SftpClient client = ssh.openSftpClient();
//Send the file
client.put(filePath);
//disconnect
client.quit();
ssh.disconnect();
Una bella astrazione su Jsch è Apache commons-vfs che offre un'API di filesystem virtuale che rende quasi trasparente l'accesso e la scrittura di file SFTP. Ha funzionato bene per noi.
C'è un bel confronto tra le 3 librerie Java mature per SFTP: Commons VFS, SSHJ e JSch
Riassumendo, SSHJ ha l'API più chiara ed è la migliore se non è necessario il supporto di altri archivi fornito da Commons VFS.
Ecco l'esempio SSHJ modificato da github :
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts(); // or, to skip host verification: ssh.addHostKeyVerifier(new PromiscuousVerifier())
ssh.connect("localhost");
try {
ssh.authPassword("user", "password"); // or ssh.authPublickey(System.getProperty("user.name"))
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.get("test_file", "/tmp/test.tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
Libreria SFTP di Apache Commons
File di proprietà java comune per tutti gli esempi
serverAddress = 111.222.333.444
userId = MYUSERID
password = miaPassword
remoteDirectory = prodotti /
localDirectory = import /
Carica il file sul server remoto utilizzando SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class SendMyFiles {
static Properties props;
public static void main(String[] args) {
SendMyFiles sendMyFiles = new SendMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + sendMyFiles.getClass().getName()+
" Properties_file File_To_FTP ");
System.exit(1);
}
String propertiesFile = args[0].trim();
String fileToFTP = args[1].trim();
sendMyFiles.startFTP(propertiesFile, fileToFTP);
}
public boolean startFTP(String propertiesFilename, String fileToFTP){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//check if the file exists
String filepath = localDirectory + fileToFTP;
File file = new File(filepath);
if (!file.exists())
throw new RuntimeException("Error. Local file not found");
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToFTP;
// Create local file object
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
remoteFile.copyFrom(localFile, Selectors.SELECT_SELF);
System.out.println("File upload successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Scarica il file dal server remoto utilizzando SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class GetMyFiles {
static Properties props;
public static void main(String[] args) {
GetMyFiles getMyFiles = new GetMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Download ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToDownload;
// Create local file object
String filepath = localDirectory + fileToDownload;
File file = new File(filepath);
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
localFile.copyFrom(remoteFile, Selectors.SELECT_SELF);
System.out.println("File download successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Elimina un file sul server remoto utilizzando SFTP
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class DeleteRemoteFile {
static Properties props;
public static void main(String[] args) {
DeleteRemoteFile getMyFiles = new DeleteRemoteFile();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Delete ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToDownload;
//Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
//Check if the file exists
if(remoteFile.exists()){
remoteFile.delete();
System.out.println("File delete successful");
}
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
hierynomus / sshj ha un'implementazione completa di SFTP versione 3 (cosa implementa OpenSSH)
Codice di esempio da SFTPUpload.java
package net.schmizz.sshj.examples;
import net.schmizz.sshj.SSHClient;
import net.schmizz.sshj.sftp.SFTPClient;
import net.schmizz.sshj.xfer.FileSystemFile;
import java.io.File;
import java.io.IOException;
/** This example demonstrates uploading of a file over SFTP to the SSH server. */
public class SFTPUpload {
public static void main(String[] args)
throws IOException {
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts();
ssh.connect("localhost");
try {
ssh.authPublickey(System.getProperty("user.name"));
final String src = System.getProperty("user.home") + File.separator + "test_file";
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.put(new FileSystemFile(src), "/tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
}
}
La libreria JSch è la potente libreria che può essere utilizzata per leggere file dal server SFTP. Di seguito è riportato il codice testato per leggere il file dalla posizione SFTP riga per riga
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("user", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
InputStream stream = sftpChannel.get("/usr/home/testfile.txt");
try {
BufferedReader br = new BufferedReader(new InputStreamReader(stream));
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException io) {
System.out.println("Exception occurred during reading file from SFTP server due to " + io.getMessage());
io.getMessage();
} catch (Exception e) {
System.out.println("Exception occurred during reading file from SFTP server due to " + e.getMessage());
e.getMessage();
}
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
Si prega di fare riferimento al blog per l'intero programma.
Andy, per cancellare il file sul sistema remoto devi usare (channelExec)
JSch e passare i comandi unix / linux per cancellarlo.
Prova edtFTPj / PRO , una libreria client SFTP solida e matura che supporta pool di connessioni e operazioni asincrone. Supporta anche FTP e FTPS, quindi sono coperte tutte le basi per il trasferimento sicuro dei file.
Ho trovato un esempio di lavoro completo per SFTP in Java usando l'API JSCH http://kodehelp.com/java-program-for-uploading-file-to-sftp-server/
Sebbene le risposte di cui sopra siano state molto utili, ho trascorso una giornata per farle funzionare, affrontando varie eccezioni come "canale interrotto", "chiave sconosciuta rsa" e "pacchetto danneggiato".
Di seguito è riportata una classe riutilizzabile funzionante per UPLOAD / DOWNLOAD FILES SFTP utilizzando la libreria JSch.
Carica utilizzo:
SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");
Utilizzo del download:
SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");
Il codice della classe:
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.swing.JOptionPane;
import menue.Menue;
public class SFTPFileCopy1 {
public SFTPFileCopy1(boolean upload, String sourcePath, String destPath) throws FileNotFoundException, IOException {
Session session = null;
Channel channel = null;
ChannelSftp sftpChannel = null;
try {
JSch jsch = new JSch();
//jsch.setKnownHosts("/home/user/.putty/sshhostkeys");
session = jsch.getSession("login", "mysite.com", 22);
session.setPassword("password");
UserInfo ui = new MyUserInfo() {
public void showMessage(String message) {
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message) {
Object[] options = {"yes", "no"};
int foo = JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo == 0;
}
};
session.setUserInfo(ui);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
channel = session.openChannel("sftp");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect();
sftpChannel = (ChannelSftp) channel;
if (upload) { // File upload.
byte[] bufr = new byte[(int) new File(sourcePath).length()];
FileInputStream fis = new FileInputStream(new File(sourcePath));
fis.read(bufr);
ByteArrayInputStream fileStream = new ByteArrayInputStream(bufr);
sftpChannel.put(fileStream, destPath);
fileStream.close();
} else { // File download.
byte[] buffer = new byte[1024];
BufferedInputStream bis = new BufferedInputStream(sftpChannel.get(sourcePath));
OutputStream os = new FileOutputStream(new File(destPath));
BufferedOutputStream bos = new BufferedOutputStream(os);
int readCount;
while ((readCount = bis.read(buffer)) > 0) {
bos.write(buffer, 0, readCount);
}
bis.close();
bos.close();
}
} catch (Exception e) {
System.out.println(e);
} finally {
if (sftpChannel != null) {
sftpChannel.exit();
}
if (channel != null) {
channel.disconnect();
}
if (session != null) {
session.disconnect();
}
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive {
public String getPassword() {
return null;
}
public boolean promptYesNo(String str) {
return false;
}
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return false;
}
public boolean promptPassword(String message) {
return false;
}
public void showMessage(String message) {
}
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo) {
return null;
}
}
}
Hai anche JFileUpload con componente aggiuntivo SFTP (anche Java): http://www.jfileupload.com/products/sftp/index.html
Uso questa API SFTP chiamata Zehon, è fantastica, così facile da usare con un sacco di codice di esempio. Ecco il sito http://www.zehon.com
La migliore soluzione che ho trovato è Paramiko . C'è una versione Java.